What security advantage do cloud service providers like Amazon, Google, and Microsoft have over local staff and systems for most small to mid-sized organizations?

In most cases, the major cloud service providers have more security staff and a greater budget for security operations. This means they can invest more in security controls, staffing, monitoring, and other activities. Using a cloud service provider can help improve the overall security posture of an organization that might not have the ability to have full-time or dedicated security staff or expertise. At the same time, local staff will understand the business better and will usually have a faster response time to critical business needs.